It's about one-three-thousandth the number of Books in the Library of Congress (2013).
In other words, 8,400 is 0.0003560519 times the count of Books in the Library of Congress (2013), and the count of Books in the Library of Congress (2013) is 2,808.5793 times that amount.(2013 figures) (total of books only)
As of September, 2013, The Library of Congress had 23,592,066 books in its catalog and a total of 158,007,115 physical items.
It's about 4,000 times the number of Escalators in the State of Wyoming.
In other words, the count of Escalators in the State of Wyoming is 0.0003 times 8,400.(2013 figures)
There are only two escalators in the State of Wyoming (although there are apparently plenty of elevators). It is speculated that the lack of escalators is due to the older age of the buildings and the abundance of cheap land resulting in single-story structures. At the time the last count of escalators was made, the state had a population of just 576,000 people.
It's about one-four-thousand-five-hundredth the number of people in The State of California.
In other words, 8,400 is 0.0002191 times the count of people in The State of California, and the count of people in The State of California is 4,564 times that amount.(2014 figures) (Department of Finance estimate)
California, the most populous state in the United States, is home to 38,340,000 people (larger than the population of the entire country of Canada, with 35,540,419 people). Over ten percent of the population — 3,904,657 people — reside in the city of Los Angeles.
It's about one-seven-thousand-five-hundredth the number of Copies of Michael Jackson's Thriller Sold (2011).
In other words, the count of Copies of Michael Jackson's Thriller Sold (2011) is 7,700 times 8,400.(sales figures as of 2011) (1982 release)
Michael Jackson's Thriller, the best-selling album of all time, has sold 65 million copies since its release. Following its release in 1982, the album — which contains hits like "Thriller," "Beat It," and "Billie Jean" — won eight (8) Grammy Awards in 1984.
It's about one-ten-thousandth the number of Copies of Wii Sports Sold.
In other words, 8,400 is 0.0001016 times the count of Copies of Wii Sports Sold, and the count of Copies of Wii Sports Sold is 9,843 times that amount.(a.k.a. Wii スポーツ, a.k.a. Wi Supotsu) (2006 edition) (sales figures as of March 31, 2015)
Wii Sports, the version that was bundled with the original Wii console, has sold 82.69 million units as of March, 2015.
It's about one-twenty-five-thousandth the number of Copies of Charles Dickens' A Tale of Two Cities Sold.
In other words, the count of Copies of Charles Dickens' A Tale of Two Cities Sold is 30,000 times 8,400.(figures as of 2015)
First published in 1859, Charles Dickens' A Tale of Two CIties is the best-selling novel of all time, for which complete sales figures are available, having sold an estimates 200 million copies. The novel itself contains 135,420 words.
It's about one-one-hundred-fifty-thousandth the number of Users on Facebook.
In other words, 8,400 is 0.00000583 times the count of Users on Facebook, and the count of Users on Facebook is 172,000 times that amount.(March, 2015 figures) (monthly active users)
Facebook had 1.44 billion active users for the month ending March, 2015. In August, 2014, Facebook began a process of removing 87 million accounts that it had found to be fake.